According to Wim Hof there’s no need to suffer when the cold starts to bite. Hof, who calls himself the Iceman and holds records for enduring low temperatures, says that anyone can learn to tolerate even extreme cold.

Hof uses a combination of meditation techniques and breathing exercises, along with a training regime involving swimming in icy water.

The 55-year-old Dutchman is not the first to make this sort of claim. Travellers have long described Tibetan yogis who survive bitter Himalayan winters practically naked; they use a forced breathing technique called tummo, or “inner fire”.

Normally, exposure to the cold causes your core temperature to fall. Hof says he can maintain his core temperature at 37C even while sitting in ice water for almost two hours; this produces exceptionally high levels of adrenaline in the process.

In 2011 researchers looking at the immune system accompanied Hof, with volunteers trained in his techniques, on a mountain challenge. The volunteers hiked in shorts in temperatures as low as -27C, took snow baths and swam in freezing water. All the volunteers successfully completed the challenge.

A green alternative to turning up the central heating when the thermometer falls? It’s a regime of meditation, special breathing and cold baths that could take some willpower.